The invention relates generally to caps and accessories, and more specifically to a sheathing device that is used with a traditional cap to conceal and protect the adjustment straps. Covering and protecting the adjustment straps on a traditional cap is known in the art. Typically, devices of a predetermined length are used to encase the straps, but leave a significant portion of the straps uncovered. The uncovered portion renders the back of the cap visually unappealing. Therefore, a need exists to cover the entire length of the straps regardless of the cap's adjustment. The present invention fulfills this need.